Sectional chalk-rack



(No Model.)

J. G. PLOWMAN.

SEOTIONAL CHALK RACK. No. 326,453." Patented Sept; 15, 1885."

Es .Attorne'ys N FETER$ whom-Litho ra h washings", D c.

JOSEPH GEE PLOVVMAN, OF WHITE PIGEON, MICHIGAN.

SECTIONAL CHALK=RACl L BFECIFICATZQN forming part of Letters Patent No.326,453, dated September 15, 1885.

Application filed March 16, 1885. (X0 model.)

T 0 all whom it may concern.-

Be it known that l, JOSEPH GEE PLOWMAN, residing at White Pigeon, in thecounty of St. Joseph and State of Michigan, have invented certain newand useful Improvements in Chalk-Racks; and I do declare the followingto be a full, clear, and exact description of the invention, such aswill enable others skilled in the art to which it appertains to make anduse the same, reference being had to the accompanying drawings, and toletters or figures of reference marked thereon, which form a part/0fthis specification.

Figure 1 of the drawings is a representation of this invention, and is afront view. Fig. 2 is a perspective view of the chalk-rack. Fig. 3 is alongitudinal vertical sectional view taken on the lines 00 m of Fig. 1,and Fig. 4 is a transverse sectional view taken on the lines 3 y ofFig. 1. i

This invention has relation to certain improvements upon my chalk-rackfor blackboards, for which Letters Patent of the United States weregranted August 26, 188i; and it consists in the construction and novelarrangement of devices, as hereinafter set forth, and pointed out in theappended claims.

In the accompanying drawings, the letter A designates the blackboard,and 13 its lower marginal ledge, having brackets or arms 0, adapted tohold the removable chalk trough E, which is provided with a falsebottom, H, of wire-cloth or other material having perforations orinterstices, or may be made of transverse slats. Usually I prefer thewire-cloth, which may be conveniently attached to the trough by formingvertical grooves V in the side walls thereof, and

bending the edges of the wire-cloth downward to enter said grooves.Usually, also, I make the trough in sections,as indicated, thesesections fitting each other at the ends by an angular joint, theprojecting angular end F of one section fitting in the angularly-notchedend of the next section, and so on until the proper length for theblackboard is fitted in place. This angular joint forms a close seam,and is designed to strengthen the rack and to guard against particles ofchalk falling through. The joints are secured by a clasp, G, on theouter lower portion, said clasp being pivoted to the bottom of onesection and secured to the next section by a turn-button, H, passingthrough a slot, I, of the vertical portion J of the clasp. This claspmay be made in other common modes, and should form a brace to the joint,in order that the sections may be supported in position with as fewbrackets or arms as possible. The ends of the sections are in some casesprovided with transverse guard-partitions or end wall K, to prevent thechalk-dust from getting down between the ends of the sections into thejoint.

S represents a guard-strip, of rubber, oilcloth, leather, listing, orother suitable material having some pliability, and yet beingsufficiently stiff to project by its inner edge from the upper edge, L,of the wall N of the rack. Usually this edge L,which is next theblackboard,is beveled to form an oblique hearing, to which said strip isattached. The projecting edge of this guard-strip will therefore extendupward obliquely against the surface of the blackboard, hugging the sameclosely by its free edge when the trough is in proper position. Allparticles of chalk-dust which may fall from the blackboard will becaught by this guard-strip and guided to the cavity of the trough, andwill therefore be prevented from falling between the trough andblackboard.

In making the trough or trough-sections I prefer to use single lengthsof wood, grooving them to form the trough-cavity, and making verticalsaw-kerfs in the side walls to receive the edges of the false bottom.

Having described this invention, what I claim, and desire to secure byLetters Patent, is-

1. The combination, with the removable chalk-trough for blackboards, ofthe flexible guard-strip S, attached to the upper edge of the inner wallof the said trough, and projecting from said edge to engage the surfaceof the blackboard, substantially as specified.

2. The sectional chalk-trough for blackboards having a bracing-claspadapted to connect the sections, substantially as specified.

3. A chalk-rack for blackboards, consisting of sections having angularjoint ends and In testimony whereof I aflix my signature in presence oftwo witnesses.

JOSEPH GEE PLOVVMA'N.

connected by bracing'clasps, substantially as speoified.

4. A chalk-rack forblackboards, consisting of one or more trough-shapedsections hav- 5 ing vertical grooves in their side walls, and

an interstitial false bottom having its edges Witnesses: bent downwardlyinto the said grooves, sub- GEO. W. BEISEL, stantially as specified.CHAS. LAVERTY.

